Casing Block

ABSTRACT

A preset recessed casing block for retaining a cutter bit is provided that can be mass-produced and easily installed in the casing of a core barrel. The block has a size and shape that provides for quick and easy insertion and welding into a casing. The block has a cavity that receives and retains a cutter bit while allowing for the removal or extraction of the cutter bit when the bit becomes worn or broken. Because the block is manufactured to fit inside the casing, wear on the block is minimized and it&#39;s lifetime extended. The cavity in the block and the shape of the block itself may have different, preset angles and pitches, to allow for the same size block to be placed in a variety of locations around the casing, thereby enabling the manufacturer to produce a variable, raking pattern of the cutter bits for improved annulus cutting.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent App. No.61/483,665 filed on May 7, 2011, the entirety of which is herebyincorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was not federally sponsored.

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to the general field of drilling equipment forthe foundation drilling and mining industries, and more specificallytoward a preset recessed casing block for retaining a cutter bit. Theinvention provides a casing block that can be mass-produced and easilyinstalled in the casing of a core barrel. The block can be molded or cutinto a size and shape that can be quickly and easily inserted into acasing, and welded into place. The block has a cavity manufactured intoit that is designed to receive and retain a cutter bit, but still allowfor the removal or extraction of the cutter bit when the bit becomesworn or broken. Because the block is manufactured to fit flush to thesurface of the casing, wear on the block is minimized and it's lifetimeis much greater than prior art blocks. The cavity in the block can bemanufactured with different, preset angles and pitches, to allow for thesame size of block to be placed in a variety of locations around thecasing, thereby enabling the manufacturer to produce a variable, rakingpattern of the cutter bits for improved annulus cutting. This featurealso provides efficient initial placement, and replacement of blocks.

Foundation drilling and mining has evolved over time and continues to bean essential industry for all modern civilizations. In the effort toimprove the production and quality of drilled foundations, there hasbeen huge investment, and advancement in the equipment and tools of thetrade.

One of the most common tools used by foundation drillers is the corebarrel. Core barrels are used to core through hard layers of dirt androck and are known for their ability to keep holes true and straight.

The following invention provides important advancements in themanufacturing and use of core barrel tools. The improved core barrel hasa “cutting end” that comprises a casing, which is a metal substrate witha number of cavities. “Casing blocks” (or simply “blocks”) can be weldedinto the cavities, and cutter bits can be inserted into the blocks. Theblocks can have a side opening that allows an operator to access thebottom portion of the cutter bit to make removal easier than withcurrently practiced methods.

The cutter teeth cut through rock and dirt as the core barrel advances.Because of the hard earth into which the holes are cut, the wear andtear on the cutter bits is considerable, and they often break and/orwear out and have to be replaced. A high-quality drilling rig can cost$1,000 or more per hour to operate, and operations have to stop wheneverthe operator has to replace a cutter bit and/or block. Thus, it ishighly advantageous to have a product that allows for a rapid andefficient replacement of blocks and cutter bits.

Core barrels that use carbide cutter bits with recessed blocks are thepreferred design in the industry at present because the blocks areprotected from excess wear and impact by the surrounding casing.Although preferred, they tend to be more expensive and difficult tomanufacture due to the additional installation steps and fabricationrequired.

One of the most important and time-consuming steps is setting theheight, angle, and pitch of each cutter bit and block. This procedurerequires two fabricators to take numerous measurements and docalculations to ensure that each cutter bit block is in the properlocation before it is welded into place. For example, a cutter bit setto cut and located at the outside cutting surface will have a muchdifferent ideal height, angle and pitch than would a cutter bit set tocut and located on the inside portion of the casing.

Under the prior art methods, one of the workers must take three separatemeasurements while he adjusts and holds the block into position. When hegives the “OK”, a second worker must tack weld the block to the casing.This current method has two disadvantages. First, considering the highoperating cost of even an average sized drilling rig, any “down time”can translate into thousands of dollars very quickly. Second, becausetwo fabricators are required, there has to be an additional personstanding by to assist the operator in case a cutter bit breaks or wearsout.

Prior art blocks are designed to be welded to the edge of a casingmaking them susceptible to wear and impact. Prior art blocks aredifficult to recess into casing and must have their height, angle, andpitch manually set to cut clearances.

Thus there has existed a long-felt need for preset recessed casingblocks that resist wear and impact, easy to manufacture and install, andprovide multiple heights, angles and pitches to allow for use in a widevariety of situations.

SUMMARY OF THE INVENTION

The current invention provides just such a solution by having a blockcapable of being placed in a cavity in a casing used for core barrelsand other drilling apparatus. The block is molded or cut into a size andshape that can be quickly and easily inserted into a casing, and weldedinto place. The block has a cavity manufactured into it that can receivea cutter bit. Because the block is manufactured to fit flush to thesurface of the casing, wear on the block in minimized. The cavity in theblock can be manufactured with different, preset angles and pitches toallow for the same size of block to be placed in a variety of locationsaround the casing, thereby enabling the manufacturer to produce avariable raking pattern of the cutter bits for improved annulus cutting.This feature also provides efficient initial placement, and replacementof blocks.

An object of the invention is to provide the industry with a presetrecessed casing block that can be installed faster and easier with onlyone worker needed to perform the work. The invention comprises a squareor rectangular outer shape to make it easy to lay out and cut casingwhen installing. Each block is designed to mount flush with the top edgeof casing so there is no need to measure or set the height. Each blockis preset with optional angles and pitches and only needs to be selectedand centered into the casing. Blocks can be preset to inside, outside,middle cutter and other miscellaneous positions. All a worker will needto do is cut the typical block size out the casing, choose a block,(outside, inside, middle, etc.) and weld it into place.

A wedge shaped tool can be used to easily remove the cutter bits fromthe blocks. By accessing the bottom of the cutter bit through the holein the side of the block, a worker can hammer or otherwise push up onthe cutter bit from the bottom, dislodging it and popping it out the topof the block cavity. Blocks can be made with or without the snap ringaccess hole in the side. The sides of the block can be beveled to allowfor welds. Block settings can be purchased with different attack angles,and can be purchased preset as outside, inside, middle, middle inside,middle outside, etc., or any other of the preferred combinations ofheight, angle and pitch found in different locations on the casing.Blocks can be made to accept any type of cutter including rotating,non-rotating, and can be made in different materials, shapes and sizes.

It is a principal object of the invention to provide a casing block thatis easily installed and removed from the casing of a drilling apparatus.

It is another object of the invention is to provide a means to allowcutter bits to be inserted and removed easily from the casing block,which can be a recessed cavity in the block that is shaped toaccommodate a cutter bit.

It is an additional object of the invention that the casing block bemade in a variety of shapes to accommodate a variety of casings anddrilling plans.

It is a further object of the invention that the casing block can bemanufactured with a wide range of angles and pitches with respect to therecessed cavity, such that a cutter bit with a desired angle of attackcan be inserted into a particular type of casing block for a particularlocation on the casing.

It is also an object of this invention that the casing block has bevelededges that allow for welding of the block into the casing.

It is yet another object of this invention that the invention allow fora more efficient drilling operation by reducing the number of workersrequired to remove and replace a casing block, and by allowing this workto be done more quickly than is currently possible using the prior artmaterials and methods.

There has thus been outlined, rather broadly, the more importantfeatures of the invention in order that the detailed description thereofmay be better understood, and in order that the present contribution tothe art may be better appreciated. There are additional features of theinvention that will be described hereinafter and which will form thesubject matter of the claims appended hereto. The features listed hereinand other features, aspects and advantages of the present invention willbecome better understood with reference to the following description andappended claims.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated in and form a part ofthis specification, illustrate embodiments of the invention and togetherwith the description, serve to explain the principles of this invention.

FIG. 1 is a perspective view of a casing block according to selectedembodiments of the current disclosure.

FIG. 2 is a partial bottom view of a core barrel with three casingblocks secured thereto according to selected embodiments of the currentdisclosure.

FIG. 3 is a partial bottom view of a core barrel with a single middlecasing block secured thereto according to selected embodiments of thecurrent disclosure.

FIG. 4 is a side view of a casing block secured to a core barrel and acutter bit according to selected embodiments of the current disclosure.

FIG. 5 is a front view of a casing block according to selectedembodiments of the current disclosure.

FIG. 6 is a cutaway side view of a casing block according to selectedembodiments of the current disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Many aspects of the invention can be better understood with thereferences made to the drawings below. The components in the drawingsare not necessarily drawn to scale. Instead, emphasis is placed uponclearly illustrating the components of the present invention. Moreover,like reference numerals designate corresponding parts through theseveral views in the drawings.

FIG. 1 is a perspective view of a casing block according to selectedembodiments of the current disclosure. The casing block 10 has a cavitymanufactured into it during production. The cavity of the casing block10 has two general parts, a retaining section 13, designed to seat thebottom half of a cutter bit, and a terminal cavity 12 designed to retaina snap ring on a cutter bit (not shown in this figure), and to allow fora wedge-shaped implement to easily pry loose any worn or broken cutterbits for removal and replacement. The block 10 has a trailing supportedge 14 that provides support to the trailing edge of the cutter bit asit is moved forward by the drilling rig. Each corner of the casing block10 has a beveled edge 11 to allow for easy welding into openings in thecore barrel.

The casing blocks are generally made of steel, iron, or some alloy, andare sometimes heat-treated. The common means by which casing blocks areretained in the casing is to weld them in place, although other means ofattachment are contemplated.

FIG. 2 is a partial bottom view of a core barrel with three casingblocks secured thereto according to selected embodiments of the currentdisclosure. The left-most casing block 10 in this figure is secured inthe casing 51 of the core barrel 50 at an inside position, whereby acutter bit retained therein is angled towards the inside of the corebarrel. The center casing block 10 in this figure is secured in thecasing 51 of the core barrel 50 at a middle position, whereby a cutterbit retained therein is angled in the same direction as the longitudinalaxis of the core barrel. The right-most casing block 10 in this figureis secured in the casing 51 of the core barrel 50 at an outsideposition, whereby a cutter bit retained therein is angled towards theoutside of the core barrel.

FIG. 3 is a partial bottom view of a core barrel with a single middlecasing block secured thereto according to selected embodiments of thecurrent disclosure. The casing block resides in the casing 51. Theretaining section 13 and the trailing support edge 14 are visible inthis figure, as well as the beveled edges 11 in each of its four outercorners.

FIG. 4 is a side view of a casing block secured to a core barrel and acutter bit according to selected embodiments of the current disclosure.The function of the block can be seen in this figure. As the drillingrig turns the drill bit, the casing rotates, pushing the cutter bitsagainst the soil and rock point first. As the point of the cutter bitdigs into the soil, the trailing support edge 14 and the retainingsection 13 keep the cutter bit 40 at the proper angle and pitch tomaximize the efficiency of the cutting. It should be noted that thecasing 51 has a variety of cutter bits located on different parts of thecasing, so that different casing blocks that have cavities that pointthe cutter bit in different directions are needed. In an ideal drillingsetup, having cutter bits pointing downward, inward, and outward to thesides produces maximum “raking” of the soil, which results in maximumefficiency.

Over time, the cutter bit 40 will either break or wear out and have tobe replaced. When it becomes necessary to remove and replace a cutterbit, the cutter bit is pulled out after removal of the snap ring. Accessfor removing the snap ring is provided through the terminal cavity 12.If after removing the snap ring the cutter but 40 is still stuck in thecasing block 10, the cutter bit may be levered out by use of awedge-shaped tool. The average casing block will last through aboutfifteen to twenty cutter bits. When it is time to replace the casingblock, the welded portion is cut through and the block removed. Anothercasing block can be quickly installed in the cavity, welded into place,have a cutter bit installed, and then the drilling operation can resume.This method is considerably more efficient than the current method ofindividually welding irregular shaped blocks and cutter bits into thepreferred combination of heights, angles and pitches.

The casing 51 has a cavity into which the casing block 10 has beeninserted. There is adequate space between the edge of the cavity of thecasing 51 and the sides of the casing block 10 for welding. The trailingsupport edge 14 buttresses the first retaining portion 16 of theretaining section in the block 10 into which the cutter bit 40 isinserted. The retaining portion 14 includes two different sections withtwo different diameters; the second retaining portion 17, which isproximate to the terminal cavity, has a smaller diameter than the firstretaining portion 16. The shank portion of the cutter bit 41, 42 (whichalso has two different sections with two different diameters) rests onand is retained by difference in diameter of the first retaining portion16 and the second retaining portion 17.

The cutter bit 40 has two different shank sections: a first shanksection 41 and a second shank section 42. The first shank section 41 hasa larger diameter than the second shank section 42. The distal end ofthe second shank section 42 includes an indentation 44 (or groove)around its entire circumference. The snap ring discussed above extendsaround this indentation 44. A rotating protective sleeve 43 facilitatesthe rotation of the cutter bit 40 within the casing block 10 while alsoreducing the wear and tear on the casing block 10 from the rotation ofthe cutter bit 40.

A more thorough description of the cutter bit can be found in U.S. Pat.No. D601,592, U.S. patent application Ser. No. 12/465,851, and EuropeanUnion Pat. No. 001113039-0001, all of which, including anypriority-related applications, are hereby incorporated by reference.

FIG. 5 is a front view of a casing block according to selectedembodiments of the current disclosure. The bottom of the casing block 10includes a flat base portion 20 and two angled base portions 19. Thebase angle 21, which is the difference in angle between the flat baseportion 20 and the angled base portion, enables the casing block 10 tobe installed into a core barrel at that angle. In other words, thecasing block 10 may be installed at an angle into the cavity of a casingsuch that one of the angled base portions mates flush with the bottom ofthe cavity. In this manner, casing blocks, and thus cutter bits, may bequickly and efficiently installed into a casing at one of threepredetermined orientations: middle, inner, and outer. It will beappreciated by those in the art that different casing blocks may bemanufactured with different base angles. Furthermore, it will beappreciated by those in the art that the same casing bock with twoangled base portions 19 may have different base angles 21 for each ofthe two angled base portions 19.

FIG. 6 is a cutaway side view of a casing block according to selectedembodiments of the current disclosure. This view is taken along line 6shown in FIG. 5. The casing block 10 includes a terminal cavity 12, afirst retaining portion 16 and a second retaining portion 17. The backend of the first retaining portion 16 is supported by the trailingsupport edge 14. The trailing support edge 14 is a raised sectionproximate to the retaining section. The pitch of the cutter bit is setby the angle of the retaining section. A low pitch results in a cutterbit that is relatively parallel to the top of the casing block. A highpitch results in a cutter bat that is almost or actually perpendicularto the top of the casing block. A medium pitch results in a cutter bitthat is somewhere between a low pitch and a high pitch.

It should be understood that while the preferred embodiments of theinvention are described in some detail herein, the present disclosure ismade by way of example only and that variations and changes thereto arepossible without departing from the subject matter coming within thescope of the following claims, and a reasonable equivalency thereof,which claims I regard as my invention.

All of the material in this patent document is subject to copyrightprotection under the copyright laws of the United States and othercountries. The copyright owner has no objection to the facsimilereproduction by anyone of the patent document or the patent disclosure,as it appears in official governmental records but, otherwise, all othercopyright rights whatsoever are reserved.

1. A device for retaining a cutter bit in a casing comprising: a bottom,four sides, a top, and a cutter bit retaining section, where the bottomand the four sides are capable of fitting into a cavity of a casing. 2.The device of claim 1, wherein one of the four sides comprises anopening through which a bottom of a shaft portion of a cutter bit can beaccessed, wherein this opening is a terminal cavity.
 3. The device ofclaim 1, where the four sides are of equal length, thereby making asquare.
 4. The device of claim 1, where the four sides have two sides ofone length and two sides of another length, thereby making a rectangle.5. The device of claim 1, wherein the device further comprises fourbeveled edges, where there is a beveled edge between each of the foursides, and where the beveled edges allow for welding material to beinserted in between the device and the casing.
 6. The device of claim 1,further comprising a trailing support edge, where the trailing supportedge is a raised section proximate to the cutter bit retaining section.7. The device of claim 1, where the device further comprises a terminalcavity, where the terminal cavity is proximate to the cutter bitretaining section, wherein the cutter bit retaining section comprises afirst retaining portion and a second retaining portion, and wherein theterminal cavity has an opening.
 8. The device of claim 7, wherein thecutter bit retaining section is shaped to mate with a shank section of acutter bit.
 9. The device of claim 7, wherein the first retainingportion and second retaining portion each have a diameter, where thediameter of the first retaining portion is greater than the diameter ofthe second retaining portion.
 10. The device of claim 1, wherein thecutter bit retaining section is manufactured in a low pitch.
 11. Thedevice of claim 1, wherein the cutter bit retaining section ismanufactured in a high pitch.
 12. The device of claim 1, wherein thecutter bit retaining section is manufactured in a medium pitch.
 13. Thedevice of claim 1, wherein the device is manufactured for an insideposition on a casing.
 14. The device of claim 1, wherein the device ismanufactured for a middle position on a casing.
 15. The device of claim1, wherein the device is manufactured for an outside position on acasing.
 16. The device of claim 1, wherein the bottom of the devicecomprises a flat base portion and two angled base portions, whereby theflat base portion and angled base portions enable the same device to beused for an inside position, middle position, or outside position in acasing.
 17. The device of claim 1, additionally comprising a terminalcavity, wherein the terminal cavity is accessible though one of the foursides.
 18. The device of claim 17, wherein a cutter bit can be removedfrom the device through the use of a wedge shaped tool.
 19. The deviceof claim 1, wherein the cutter bit retaining section is designed toaccommodate a rotating cutter bit.
 20. The device of claim 1, whereinthe cutter bit retaining section is designed to accommodate anon-rotating cutter bit.